Using differential variability to increase the power of the homogeneity test in a two-sample problem

  title={Using differential variability to increase the power of the homogeneity test in a two-sample problem},
  author={Guanfu Liu and Yuejiao Fu and Pengfei Li and Xiaolong Pu},
  journal={Statistica Sinica},
We consider a particular two-sample homogeneity testing problem often encountered in case-control studies with contaminated controls, or in detecting a treatment effect when some subjects are not affected by the treatment in biological experiments. We propose an EM-test designed to simultaneously detect mean difference and differential variability in the two samples. We show that the EM-test statistic has a chi-squared null limiting distribution. The asymptotic properties of the EM-test under… 

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